vulkan

Hi *,

asymptote-3.12 has a configure option --enable-vulkan, which is on by 
default. I have no vulkan stuff installed, except dev-util/vulkan-headers; 
with this default setting, configure fails to find libvulkan, and building 
asymptote fails. I've added --disable-vulkan to the ebuild, and then 
emerge succeeds. I suppose it would be reasonable to add the USE flag 
vulkan. But I know nothing about vulkan, anc certainly cannot test it. 
What should I DEPEND on with USE=+vulkan? What package contains libvulkan?

Andrey